"SA Development" wrote in message
...
Hi Frank,

Calculate the area of the supply duct then cut the same area from the
bottom of the door. for instance if you have a six inch internal
diameter duct feeding your office the supply area would be 28.26
square inches so if your 30" door has an inch gap above finish floor
you should have enough return area. an eight inch diameter duct would
require about 1-3/4" above finished floor level. If you cannot get
enough by doing that put a return grill in your door. a lot simpler
than putting in a return duct.

This was my first idea, but I use the office to work in and I have to keep
the noise of a toddler out of it, so I can't cut the door or put a door
vent in.

Any other ideas?

Thanks,

Alan


If not through the door then down through the floor and back up the other
side of the wall. or into one wall cavity and out another (as long as it is
not a fire rated wall)

I don't have return air but adding a vent was easy. I just selected
apporpriate sized and shaped sheet metal for the end in the wall and
flexible 6" duct for the middle and a 6" WYE to connect it to the old duct
(I removed a section and used the WYE and a short section of flex to replace
the excised section). Don't forget the clamps and real Duct tape (has a
specification number on the label)

The cardboard like material may be some kind of applied insulation panel.
metal may be underneith.